Exercise equipment with dual fans for changing fluid resistance

ABSTRACT

The present invention is to provide an exercise equipment with dual fans for changing fluid resistance, which includes a housing, two fans and two driving members. The housing forms a receiving cavity therein for receiving fluid. Each fan includes a shaft pivotally provided at a central position of the housing and driven by a driven wheel and a plurality of vanes each fixedly provided on the periphery of the shaft and received in the receiving cavity. The driven wheels can drive the corresponding vanes to rotate about the corresponding shafts, thereby causing the fluid in the receiving cavity to form vortices. The driving members are movably provided outside the housing and connected with the corresponding driven wheels respectively by a link assembly. When the driving members are pushed or pulled, the link assemblies drive the corresponding driven wheels respectively and thereby drive the shafts to rotate with the driven wheels.

FIELD OF THE INVENTION

The present invention relates to an exercise equipment, more particularly to an exercise equipment with dual fans for changing fluid resistance, wherein fluid resistance is changed by convection caused by the two fans.

BACKGROUND OF THE INVENTION

Nowadays, muscle training equipment is available in various forms. In addition to the commonly seen weight training apparatuses that employ weight disks, exercise equipment which uses fluid as a source of resistance has been designed and is now in wide use. The fluid resistance-based exercise equipment typically includes driving members such as handles or pedals for driving a single fan to rotate against the fluid in a sealed housing, and the intended exercising effect can be achieved by the user's trying to overcome the resistance of the fluid against the vanes of the fan.

However, the aforesaid exercise equipments have the following three shortcomings that tend to compromise training effect:

1. Low resistance: To prevent leaking, the fluid resistance-based exercise equipment only uses a small amount of fluid, so the resistance provided by the fluid is low. Moreover, as the vortex generated by the fluid flow spins in the same direction as the fan, the inertia of the fluid reduces the resistance applied to the fan. When the resistance is low, only a small number of muscle fibers in the user's active muscle groups are called upon to exert force; in other words, the training effect is poor.

2. Inappropriate intensity: The strength of human muscles varies greatly with the angles of joints across which the muscles span. For example, the strength of the biceps is about 1.4 times as high when the arm is bent at right angle as when the arm is straight. Nevertheless, due to gravity or inertia, the resistance provided by existing exercise equipment tends to decrease rather than increase as the user bends his or her arms to exert more force. Consequently, the user's active muscle groups are not effectively stimulated during exercise. One solution is to set the training intensity at a higher level, which, though effective in stimulating the active muscle groups, can be too stimulative or even harmful to straightened arms.

3. Overly simple motion: In order to activate the maximum number of motor units in the human body, increase energy consumption, and strengthen the brain's control over muscles, a reciprocating motion involving the user's alternate push and pull is typically used, in which the flexor and extensor muscle groups and the rotator muscle groups work in an alternate and coordinated fashion that increases the complexity of muscular movement. However, the fluid or weight disks of the conventional exercise equipment are subject to inertial movement such that, whenever the user stops moving or changes the direction of motion, eccentric muscle contraction takes place instantaneously. As eccentric contraction is correlated to muscle lacerations and muscle strains, the safety of the aforesaid reciprocating motion is not guaranteed, unless muscle groups are trained in one direction at a time. Nonetheless, eccentric contraction is inevitable when the weight disk-based equipment is used.

So far, the shortcomings stated above can only be overcome by using an electromechanical system to control the magnitude and direction of resistance of an exercise equipment. And yet exercise equipment having such electromechanical systems are affordable only to hospitals or research institutions, entail complex installations, are good for exercising one limb at a time, and hence can only serve as rehabilitation or testing equipment.

Therefore, the issue to be addressed by the present invention is to provide a non-electrically driven simple structure that can solve the aforementioned problems effectively.

BRIEF SUMMARY OF THE INVENTION

In view of the unsatisfactory training effect of the conventional exercise equipment, the inventor of the present invention incorporated years of practical experience into repeated experiments and tests and finally succeeded in developing an exercise equipment with dual fans for changing fluid resistance, as an improvement over the existing exercise equipment in terms of both safety and training effect.

It is an object of the present invention to provide an exercise equipment with dual fans for changing fluid resistance, wherein fluid resistance is changed by convection caused by the two fans. The exercise equipment includes a housing, two fans, and two driving members. The housing forms a receiving cavity therein for receiving fluid (e.g., water). Each fan includes a shaft and a plurality of vanes. The vanes of each fan are fixedly provided on the periphery of the corresponding shaft and are received in the receiving cavity. The shafts are pivotally provided at a central position of the housing and are each provided with a driven wheel. The driven wheels can drive the corresponding vanes to rotate about rotation axes defined respectively by the corresponding shafts, thereby causing the fluid in the receiving cavity to form vortices. The driving members are movably provided outside the housing and can be pushed and pulled reciprocally outside the housing. Each driving member and the corresponding driven wheel are connected by a link assembly. When the driving members are pushed or pulled, the link assemblies drive the corresponding driven wheels respectively and thereby drive the shafts to rotate with the driven wheels.

It is another object of the present invention to provide the foregoing exercise equipment, wherein the exercise equipment is fixed at a specific location (e.g., on an exercise bench), and the driving members, when pushed or pulled by the user with both hands, cause the vanes to generate two opposing or separate vortices in the receiving cavity. As the speed of the vortices depends on the force applied by the user and in turn influences the resistance against vane rotation, the resistance increases with the force applied.

Yet another object of the present invention is to provide the foregoing exercise equipment, wherein the vortices generated by the vanes interact with each other and generate turbulent flows that interrupt inertial flow of the fluid. In addition, directional wheels are provided and configured in such a way that, whether the user pushes or pulls the driving members, the user's active muscles always undergo concentric contraction and are therefore prevented from damage which may otherwise result from eccentric muscle contraction. Further, should the user feel any discomfort or weakness at a certain joint angle, the user is free to stop the exercise or reduce the resistance as needed.

Still another object of the present invention is to provide the foregoing exercise equipment, wherein when the user is engaged in multi joint flexion and extension actions of both left and right limbs, the user's torso rotation muscle groups and stabilizing muscle groups are required to work in concert with the limbs. With the user's body being rotated during limb flexion and extension, a high degree of muscle contraction is achieved. Meanwhile, the instructions given by the user's brain to the muscles are more diversified and more complex than in an exercise which involves flexion and extension of a single muscle group on each side of the body (e.g., in a dumbbell bench press). Therefore, not only can coordination between different muscle groups be substantially improved, but also energy consumption is increased. Moreover, as the present invention uses the opposing vortices to counteract the inertia of the fluid, the aforesaid actions can be carried out in safety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The structure as well as a preferred mode of use, further objects, and advantages of the present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates the technical principle employed in the present invention;

FIG. 2 is an exploded perspective view of the first embodiment of the present invention;

FIG. 3A schematically shows a mode of installation of a shaft in the first embodiment of the present invention;

FIG. 3B schematically shows another mode of installation of the shaft in the first embodiment of the present invention;

FIG. 4 is a perspective view of a link assembly according to the first embodiment of the present invention;

FIG. 5 is a perspective view of a link assembly according to the second embodiment of the present invention;

FIG. 6 is a perspective view of a link assembly according to the third embodiment of the present invention;

FIG. 7A is a perspective view of a link assembly according to the fourth embodiment of the present invention;

FIG. 7B is a perspective view of a roller and cables according to the fourth embodiment of the present invention;

FIG. 8 schematically shows how an exercise equipment according to the present invention can be operated;

FIG. 9 is an exploded perspective view of the fifth embodiment of the present invention;

FIG. 10 is a sectional view of the fifth embodiment of the present invention;

FIG. 11A is a perspective view of the sixth embodiment of the present invention; and

FIG. 11B is a perspective view of the internal components of the sixth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides an exercise equipment with dual fans for changing fluid resistance. In a nutshell, the two fans are configured to disturb fluid and generate a plurality of vortices in the fluid so that a proper resistance against the fans is created by interaction between the vortices. Before the hardware structure of the exercise equipment is disclosed, the technical principle of the present invention is described with reference to FIG. 1. As shown in the drawing, two fans 12 are immersed in fluid and each include a shaft 120 and a plurality of vanes 121. The vanes 121 of each fan 12 are fixed to the periphery of the corresponding shaft 120. When the fans 12 are rotated separately (e.g., in directions indicated by the arrows in FIG. 1), the fluid is disturbed by rotation of the fans 12 and spins with the fans 12, thus forming a plurality of vortices. By changing the angle of attack of each vane 121, the vortices can be made to spin toward or away from each other or in separate directions. As the vortices interact with each another and keep disturbing the fluid, turbulent flows occur, and the spinning directions of the turbulent flows or of the vortices are not exactly the same as those of the fans 12. Consequently, not only is the resistance applied to the vanes 121 high, but also the vanes 121 are prevented from inertial rotation. The exercise equipment of the present invention takes advantage of the aforesaid interactions between the fans 12 and the vortices so as to provide enhanced safety and better exercising effect.

Referring to FIG. 2 for the first embodiment of the present invention, an exercise equipment 2 includes a housing 21, two fans 22, and two driving members 23 (e.g., handles). The housing 21 defines a receiving cavity 211 therein. The receiving cavity 211 is configured for receiving fluid (e.g., water) and the fans 22. The fans 22 are located near two opposite lateral sides of the housing 21 respectively, and each fan 22 includes a shaft 220 and a plurality of vanes 221. The vanes 221 of each fan 22 are provided on the periphery of the corresponding shaft 220. The shafts 220 are pivotally provided at a central position of the housing 21, and each shaft 220 has a driven wheel 223 at one end. When the driven wheels 223 are driven, the vanes 221 are rotated about rotation axes defined by the corresponding shafts 220 respectively, thereby causing the fluid in the receiving cavity 211 to form vortices. It should be pointed out that pivotal connection between the shafts 220 and the housing 21 may take various forms, and the related components (e.g., the housing 21) may vary accordingly, with a view to meeting design requirements. For example, the shaft 220 in FIG. 3A has one end embedded in a lateral side of the housing 21 and connected with a bearing 213 to facilitate rotation of the shaft 220. Alternatively, referring to FIG. 3B, a frame 21A is inserted through a lateral side of the housing 21 from outside, with a watertight washer provided between the frame 21A and the housing 21 to ensure watertightness, and a rod 220A passes through both shafts 220 and has one end fixed to the frame 21A, wherein each shaft 220 is also connected with a bearing 213A to facilitate rotation. In other words, the structure of the shafts 220 may differ from those illustrated herein without departing from the scope of the present invention, as long as the shafts 220 are pivotally provided at a central position of the housing 21. Moreover, it is feasible to use a different mode of pivotal connection in another embodiment of the present invention. However, in order to simplify graphic illustration, the aforesaid features of the housing 21 and of the shafts 220 will be omitted in the drawings of the embodiments described below.

Referring to FIGS. 2 and 4, the driving members 23 in the present embodiment are handles. Nonetheless, a person skilled in the art who has fully understood the technical features disclosed herein may change the configuration of the driving members 23 when implementing the present invention. For example, the driving members 23 can be formed as pedals, pulling cords, and so forth. The driving members 23 are movably provided adjacent to the top of the housing 21 and can be pushed and pulled reciprocally outside the housing 21. Between the driving members 23 and the fans 22 is a link assembly 25 which includes a plurality of cables 251, a plurality of directional wheel units 252, two driving wheels 253, and an axle 257. The cables 251 are connected to the driving members 23 and the directional wheel units 252 respectively. Each directional wheel unit 252 is mounted on one of the driving wheels 253 such that the driving wheels 253 and the directional wheel units 252 always rotate in the same directions, as explained in more detail below. Both driving wheels 253 mesh with one end of the axle 257 so as to drive the axle 257 into rotation, and the other end of the axle 257 meshes with the driven wheels 223 so as to drive the driven wheels 223 into rotation. Each directional wheel unit 252 is composed of an upper directional wheel 2521 and a lower directional wheel 2523, wherein the directional wheels 2521 and 2523 in each pair are independent of each other in terms of spinning direction. Furthermore, only when the directional wheels 2521 or 2523 are rotated in a certain direction (e.g., clockwise) will they be able to drive the corresponding driving wheels 253. When rotated in the opposite direction (e.g., counterclockwise), the directional wheels 2521 and 2523 spin idly without driving the corresponding driving wheels 253.

With reference to FIGS. 2 and 4, each of the directional wheels 2521 and 2523 is wound with a cable 251. Since the two directional wheel units 252 and their corresponding cables 251 operate in the same way, the following description is directed to only one directional wheel unit 252 and the corresponding cables 251. When a user pushes one of the driving members 23, the upper cable 251 drives the upper directional wheel 2521 to rotate clockwise. Meanwhile, the lower cable 251 drives the lower directional wheel 2523 to rotate counterclockwise. As a result, the axle 257 is driven to rotate clockwise by the upper directional wheel 2521 and drives the driven wheels 223 accordingly. When the driving member 23 is pulled, the upper cable 251 drives the upper directional wheel 2521 into counterclockwise rotation, and the lower cable 251 drives the lower directional wheel 2523 into clockwise rotation; consequently, the axle 257 is driven to rotate clockwise by the lower directional wheel 2523 and drives the driven wheels 223 accordingly. Hence, no matter the driving members 23 are simultaneously pushed or pulled, or one of the driving members 23 is pushed while the other is pulled, the fans 22 will always be driven to rotate and generate vortices conductive to the intended exercising effect. It should be noted that while the two driving wheels 253 in this embodiment share the same axle 257, it is feasible to provide two axles 257 in a different embodiment of the present invention so that each driving wheel 253 corresponds to a different axle 257. It is also feasible for each directional wheel unit 252 to have only one directional wheel and work with only one cable 251.

Referring to FIG. 2, each driving member 23 includes a grip 232. Each grip 232 is pivotally connected by a pivot 233 to one end of the corresponding driving member 23 and can be rotated about a rotation axis defined by the pivot 233. The grips 232 are designed to be gripped by the user to facilitate pushing or pulling the driving members 23. Besides, as the grips 232 are pivotally provided on the corresponding driving members 23, the user is allowed to turn his or her wrists, elbows, and shoulder joints freely as a way to maximize muscle contraction and increase the complexity of muscular movement. Moreover, with the link assembly 25 jutting out of the top of the housing 21, the housing 21 in the present embodiment can store a large amount of fluid, which gives high resistance to the fans 22 and leads to effective muscle training

In addition to the foregoing configuration, the technical features of the present invention can be embodied by structural variants of the housing, the driving members, and the fans, installed at positions different from those described above. For example, the driving members can be provided to the left and right of the housing respectively. The components of the link assembly may also be modified, and the driven wheels may take other forms, so as to satisfy the needs of different types of exercise equipment. Referring to FIG. 5 for the second embodiment of the present invention, a link assembly 35 includes two racks 351 and a driving wheel 353. The racks 351 are provided on a driving member 33 and located opposite each other (e.g., at corresponding upper and lower positions as shown in FIG. 5). The driving wheel 353 is pivotally provided adjacent to the driving member 33 and a driven wheel 323 and meshes with one of the racks 351 and the driven wheel 323 respectively, wherein the driven wheel 323 is in the form of a gear in this embodiment. When the driving member 33 is pushed or pulled, displacement of the racks 351 drives the driving wheel 353 and the driven wheel 323 into rotation sequentially. As a result, the driven wheel 323 drives the shaft to rotate, and vortices are generated by the vanes 321. If it is desired to alter the rotation direction of the driven wheel 323, the driving wheel 353 can be changed to a different position such that the driving wheel 353 meshes with a different portion of the racks 351. It is also feasible to provide only one rack 351 in a different embodiment of the present invention.

The embodiments that follow are provided mainly to illustrate variations of the link assembly, in which components other than the link assembly remain substantially the same in terms of both structure and connection. Therefore, new reference numerals are given only to the link assemblies but not to the other components. Please refer to FIG. 6 for the third embodiment of the present invention. The link assembly 45 includes two racks 451, a driving wheel 453, and a belt 455. The racks 451 are provided on the driving member 33 and are positioned opposite each other (e.g., at corresponding upper and lower positions as shown in FIG. 6). The driving wheel 453 is pivotally provided adjacent to the driving member 33 and the driven wheel 323 and meshes with one of the racks 451. In addition, the driving wheel 453, which is configured as a belt pulley in this embodiment, is connected to the driven wheel 323 by the belt 455. Thus, by means of the link assembly 45, the driving member 33 can drive the vanes 321 to rotate. In this embodiment, it is also feasible to have only one rack 451.

As friction between racks and gears tends to produce noise, the foregoing racks can be replaced by cables. In the fourth embodiment of the present invention as shown in FIGS. 7A and 7B, the link assembly 55 includes two cables 551 and a roller 553. The cables 551 are wound around the periphery of the roller 553 (see FIG. 7B), and each cable 551 has one end fixed to the roller 553 and the other end connected to one of the two opposite ends of the driving member 33. A central portion of the roller 553 is mounted around the driven wheel 323. Thus, when the driving member 33 is pushed or pulled, the length of each cable 551 that is wound around the roller 553 is changed, causing the roller 553 to rotate and thereby drive the driven wheel 323 into rotation. This can also be achieved with only one cable 551. In that case, a central section of the cable 551 is wound around the roller 553 while the two ends of the cable 551 are connected to the two ends of the driving member 33 respectively. Besides, instead of being mounted around the driven wheel 323, the central portion of the roller 553 can be mounted on a driving wheel as in the previous embodiments so that the driven wheel 323 is driven by the driving wheel. Therefore, the link assembly 55 may vary in structure without departing from the scope of the present invention, provided that the roller 553 is connected to the driven wheel 323 and can drive the driven wheel 323 to rotate.

According to the above, once the exercise equipment 3 of the present invention is fixed to an exercise bench 301 as shown in FIG. 8, a user can push and/or pull the driving members 33 simultaneously or alternately with both hands. By changing the link assembly that works in conjunction with each driving member 33 (e.g., using the link assembly shown in FIG. 5, 6, or 7A, or in the first embodiment of the present invention), the vanes 321 on the shafts can be rotated in the same direction or opposite directions, thereby generating one or two vortices in the receiving cavity. When the fans are rotated in the same direction, only one vortex is produced, and the resultant resistance is low but suitable for aerobic training When two or more than two vortices are generated, the resultant turbulent flows give rise to high resistance while the fluid is prevented from inertial flow, so high-intensity strength training can be carried out.

Aside from the configurations described above, the housing and the vanes may take other shapes according to production needs. For example, in the fifth embodiment of the present invention as shown in FIGS. 9 and 10, the structure of the housing alone is changed. Hence, for the sake of simplicity, only the related components are depicted in the drawings and described as follows. Referring to FIGS. 9 and 10, the housing 61 is composed of two housing portions 611. Each housing portion 611 has a lateral side concavely provided with a fluid action space 6110. Also, each housing portion 611 is formed therein with an inner casing 613 that is received in the corresponding fluid action space 6110. Each inner casing 613 defines a fluid storage space 6130 therein, and the lower side of each inner casing 613 has a fluid outlet 6132 for bringing the corresponding fluid storage space 6130 and fluid action space 6110 into communication. Further, a fluid inlet 6134 is formed on a lateral side of each inner casing 613 that is distant from the corresponding housing portion 611. Each fluid inlet 6134 is located at a higher position than the corresponding fluid outlet 6132, thus allowing the fluid discharged through the fluid outlets 6132 into the fluid action spaces 6110 to flow into the fluid storage spaces 6130 via the corresponding fluid inlets 6134.

As shown in FIGS. 9 and 10, two fans 62 are installed in the housing portions 611 respectively, wherein each fan 62 includes a shaft 620 and a plurality of vanes 621. Each shaft 620 has one end peripherally provided with the corresponding vanes 621. The other end of each shaft 620 passes sequentially through a central portion of the corresponding inner casing 613 and a central portion of the corresponding housing portion 611 and is exposed on the housing 61 so as to be rotated and thereby rotate the corresponding vanes 621. The vanes 621 in this embodiment are received in the fluid action spaces 6110. Thus, when the vanes 621 are rotated, the fluid in the housing 61 is driven to flow. For example, the fluid in a lower part of the fluid action spaces 6110 is driven to an upper part of the fluid action spaces 6110. As a result, the fluid in each fluid storage space 6130 flows through the corresponding fluid outlet 6132, enters the fluid action spaces 6110, and owing to the centrifugal forces, remains adjacent to the outer edges of the vanes 621 to provide proper resistance. In addition, part of the fluid and air in the fluid action spaces 6110 can flow into the fluid storage spaces 6130 via the corresponding fluid inlets 6134 (as indicated by the short arrows in FIG. 10) to prevent the housing 61 from cracking which may otherwise occur if the housing 61 fails to withstand the pressure of the fluid.

Referring again to FIG. 10, in order to ensure watertightness between the shafts 620 and the housing 61, a watertight washer 64 is provided in each housing 61 and corresponds in position to the corresponding fluid storage space 6130. Each watertight washer 64 has a surface portion which is adjacent to the outer rim of the washer and fixed to the housing 61. Each watertight washer 64 also has a surface portion which is adjacent to the center of the washer and attached to the corresponding shaft 620 while still allowing the shaft 620 to rotate. Due to their flexibility, the watertight washers 64 can remain securely attached to the corresponding shafts 620 regardless of the rotation speeds of the shafts 620 or pressure variations inside the fluid storage spaces 6130. Thus, watertightness is achieved, and the fluid in the fluid storage spaces 6130 is prevented from seeping out of the housing 61.

The sixth embodiment of the present invention discloses yet another configuration of the link assembly, as shown in FIGS. 11A and 11B. The exercise equipment 7 includes a housing 71, two fans 72, and two driving members 73. The housing 71 defines a receiving cavity therein for receiving fluid and the fans 72. As the foregoing embodiments have disclosed various housing configurations, the connection between the receiving cavity and the fans 72 should be readily understandable and therefore is not illustrated in FIG. 11A. Each fan 72 includes a shaft 720 and a plurality of vanes 721. The vanes 721 of each fan 72 are provided on the periphery of the corresponding shaft 720. The shaft 720 of one of the fans 72 passes through the shaft 720 of the other fan 72, but the former fan 72 is not configured to drive the latter fan 72. Each shaft 720 is provided with and driven by a driven wheel 723, so as for the vanes 721 of each fan 72 to rotate about an axis defined by the corresponding shaft 720.

As shown in FIGS. 11A and 11B, the driving members 73 are handles respectively and movably provided adjacent to two lateral sides of the housing 71. Between the driving members 73 and the fans 72 is a link assembly 75 which includes a plurality of first cables 751, a plurality of pulleys 752, a plurality of driving wheels 753, and a plurality of second cables 754. Each first cable 751 is connected to the corresponding driving member 73 and wound around the corresponding pulleys 752 and the corresponding driving wheel 753. Thus, when the driving members 73 are pushed or pulled by a user holding the driving members 73, the driving wheels 753 are driven into rotation by means of the first cables 751 and the pulleys 752. Each second cable 754 is wound around the corresponding driving wheel 753 and the corresponding driven wheel 723 so that each driving wheel 753 can drive the corresponding second cable 754 and thereby drive the corresponding driven wheel 723, and hence the corresponding fan 72, to rotate, causing the fluid in the receiving cavity to form one or two vortices that enable aerobic training or high-intensity muscle training

While the invention herein disclosed has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims. 

1. An exercise equipment with dual fans for changing fluid resistance, comprising: a housing formed therein with a receiving cavity for receiving fluid; two fans provided in the receiving cavity, each said fan comprising a shaft and a plurality of vanes, the vanes of each said fan being distributed around and fixed to a periphery of a corresponding said shaft and being adjacent to one of two opposite lateral sides of the housing, each said shaft being pivotally connected to a central position of one said lateral side of the housing and provided with a driven wheel, each said driven wheel being configured to drive a corresponding said shaft into rotation such that corresponding said vanes are rotated about a rotation axis defined by the shaft, thereby causing the fluid in the receiving cavity to form vortices; and two driving members movably provided outside the housing and configured to be pushed and pulled reciprocally outside the housing, there being a link assembly between each said driving member and a corresponding said driven wheel, the link assemblies being configured to drive the driven wheels respectively and thereby cause the shafts to rotate with the driven wheels respectively when the driving members are pushed or pulled.
 2. The exercise equipment of claim 1, wherein each said link assembly comprises: an axle having a first end and a second end, wherein the first end is connected to a corresponding said driven wheel and configured to drive the driven wheel into rotation, and the second end passes through the housing and is exposed on the housing; a driving wheel connected to the second end of the axle and configured to drive the axle into rotation; a directional wheel unit connected to the driving wheel and configured to drive the driving wheel into rotation; and at least a cable wound around the directional wheel unit and connected to two opposite ends of a corresponding said driving member, wherein the at least a cable is displaced and thereby drives the directional wheel unit into rotation when the driving member is pushed or pulled.
 3. The exercise equipment of claim 2, wherein each said directional wheel unit comprises: an upper directional wheel wound with a said cable and configured to drive a corresponding said driving wheel into rotation if and only if the upper directional wheel is rotated in a predetermined direction; and a lower directional wheel wound with another said cable and configured to drive the driving wheel into rotation if and only if the lower directional wheel is rotated in the predetermined direction.
 4. The exercise equipment of claim 1, wherein each said link assembly comprises: at least a rack provided on a corresponding said driving member; and a driving wheel pivotally connected to the housing at a position adjacent to the driving member and a corresponding said driven wheel and meshing with the at least a rack and the driven wheel respectively, wherein the at least a rack is displaced and thereby drives the driving wheel and hence the driven wheel into rotation when the driving member is pushed or pulled.
 5. The exercise equipment of claim 1, wherein each said link assembly comprises: at least a rack provided on a corresponding said driving member; a belt; and a driving wheel pivotally connected to the housing at a position adjacent to the driving member and a corresponding said driven wheel, meshing with the at least a rack, and connected to the driven wheel by the belt, wherein the at least a rack is displaced and thereby drives the driving wheel and hence the driven wheel into rotation when the driving member is pushed or pulled.
 6. The exercise equipment of claim 1, wherein each said link assembly comprises: a roller installed on a corresponding said driven wheel and configured to drive the driven wheel into rotation; and at least a cable having a central section wound around a periphery of the roller and two ends fixed respectively to two ends of a corresponding said driving member, wherein the at least a cable is displaced and thereby drives the roller and hence the driven wheel into rotation when the driving member is pushed or pulled.
 7. The exercise equipment of claim 1, wherein each said link assembly comprises: a roller installed on a corresponding said driven wheel and configured to drive the driven wheel into rotation; and two cables wound around a periphery of the roller, each said cable having an end fixed to the roller and an opposite end fixed to one of two opposite ends of a corresponding said driving member, wherein the cables are displaced and thereby rotate the roller and hence the driven wheel into rotation when the driving member is pushed or pulled.
 8. The exercise equipment of claim 1, wherein each said link assembly comprises: a plurality of pulleys; a first cable provided on a corresponding said driving member and wound around each said pulley; a driving wheel around which the first cable is wound, wherein the first cable is displaced to drive each said pulley and thereby drive the driving wheel into rotation when the driving member is pushed or pulled; and a second cable wound around the driving wheel and a corresponding said driven wheel, wherein the second cable is displaced and thereby drives the driven wheel into rotation when the driving wheel is rotated.
 9. The exercise equipment of claim 1, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 10. The exercise equipment of claim 2, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 11. The exercise equipment of claim 3, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 12. The exercise equipment of claim 4, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 13. The exercise equipment of claim 5, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 14. The exercise equipment of claim 6, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 15. The exercise equipment of claim 7, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 16. The exercise equipment of claim 8, wherein the housing is composed of two housing portions each having a lateral side concavely provided with a fluid action space, each said housing portion being provided therein with an inner casing, each said inner casing having: a fluid storage space defined therein; a lower side formed with a fluid outlet for bringing the fluid storage space into communication with a corresponding said fluid action space; and a lateral side which is distant from a corresponding said housing portion and formed with a fluid inlet for bringing the fluid storage space into communication with the fluid action space, the fluid inlet being located at a higher position than the fluid outlet.
 17. The exercise equipment of claim 9, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 18. The exercise equipment of claim 10, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 19. The exercise equipment of claim 11, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 20. The exercise equipment of claim 12, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 21. The exercise equipment of claim 13, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 22. The exercise equipment of claim 14, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 23. The exercise equipment of claim 15, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 24. The exercise equipment of claim 16, further comprising a watertight washer provided in each said fluid storage space, wherein each said watertight washer is flexible, has a surface portion adjacent to an outer rim of the watertight washer and fixed to the housing, and has a surface portion adjacent to a center of the watertight washer and attached to a corresponding said shaft while still allowing the shaft to rotate with a corresponding said driven wheel.
 25. The exercise equipment of claim 17, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 26. The exercise equipment of claim 18, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 27. The exercise equipment of claim 19, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 28. The exercise equipment of claim 20, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 29. The exercise equipment of claim 21, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 30. The exercise equipment of claim 22, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 31. The exercise equipment of claim 23, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot.
 32. The exercise equipment of claim 24, further comprising a grip pivotally connected by a pivot to an end of each said driving member, each said grip being rotatable about a rotation axis defined by a corresponding said pivot. 